Salty seaweed ales, two-pot flat whites and barrel-aged feijoa beer are just some of the creative ales on offer at Beervana this year.

The two-day beer celebration kicked off at Westpac Stadium yesterday, and included the salty seaweed ale, made by Upper Hutt's Kereru brewery, using an edible purple seaweed from the Kaikoura coast.

Production brewer Duane Morton said the use of saltwater in beer, while rare in New Zealand, originated in Germany. The seaweed gave the ale flavour and body. "It is surprisingly refreshing for something that has saltwater in it."

Saleswoman Vicki Yarker-Jones said the purple seaweed was of top quality. "It is the Ferrari of seaweed. You are not going to put a Mini in a Lamborghini beer."

For Wellingtonians who can't decide whether they prefer coffee or beer, the Garage Project has come up with a two-pot flat white so they can experience the best of both worlds.

Brewery founder Jos Ruffell said he had designed two separate beers that were intentionally brewed to be blended. A strong shot of imperial coffee stout was topped with a velvety milk cream ale, using a cafe-style milk jug.

The unique beer had been one of their most popular yesterday.

For those wanting something stronger, 8 Wired Brewery offered a wild feijoa sour beer. The barrel-aged beer has a 9.5 per cent alcohol content, the highest at the festival.

Brewery co-owner Monique Eriksen said the beer had been aged for two years in Marlborough pinot noir barrels, giving it certain oaky characteristics.

Tickets to today's event are $45 and include an official Beervana drinking vessel, a programme and a festival currency card to buy drinks and food.

More than 60 breweries are showing off their season's work, and a selection of Wellington eateries have been chosen by chef Martin Bosley to complement the craft beers.